Particle rotation normal issue with particle orientation
Some Suggestions


I have experienced some latency and strange behavior with Particles.  Yet I do not want to produce a defect report.  Sometimes I have closed and reopened file.  Move the timeline to frame 0 and switched from Vertex to Face to Volume emission.  I have been very hesitant to inquire about this.  I have felt this latency has suddenly function as expected.  Misleading latency.  Could be interpreted as superstitious.
For the text to mesh.  Edit Mode, Use vertex remove doubles.
Object Mode,  Remesh Modifier and Apply.  So your faces are even size and no tedious hand modeling.
Edit Mode, With the faces from above in Faces Mode.  Select all Faces.  Sort Elements Randomize.
Note my Emission Panel Setting are a bit different than yours.
For the current settings and the simple scaled cube ... a rotation in EDIT mode can rotate the particle.




Image above shows the results of Remesh Modifier with Apply.

Other Edits May Follow.